Arc welding



"Jul 12, 1927.

E B. PAXTQN ARC WELDING Filed Feb. 5 1927 Inventor. Earl BPaxton,

His Attor'ngs I so throu hout their length.

40 values, at

Patented July 12,1927.

L UNITEIDFSTVATESV PAJJ'IENT OFFICE. Y.

I near. a. 'ra'x'ron, or scnmsnc'ranr, m ronx, assrenon 'roemrnnannnnc'rnrc I comm, a oonrona'rron or new YORK.

ABC 'WELDIN'G.

mum... m February a, 1927. Serial no. mean.

I t is more diflicult to operate with an ala direct curf ternatingcurrent are than with rent arcbecause of the instability of the alsternating current are. This instabilit of the alternatin current are isdue large y to i the cooling'o the gaseous arc path during the time whenthecurrent passes through zero value when'the arc is more likely tobreak than with direct current.

I ropose to obtain alternatmg current are stability in single phasesystems of arc welding and cutting producing by a suitable arrangementof the welding circuit a plurality of arcs with relative phasedisplacement operating in parallel and acting upon the same portion of'the work.- By such an arrangement the conductivity of the arc path foreither arc while the current passes through zero will be maintained byanother are 1n which the current does'not' through zero at the sametime.

According. to my invention, instead of usin tor,

use an electrode formed of a plurality of conductors insulated one fromanother To these conductors ap 1y currents that are suitably de phased,re

sequently described, so that when the are between the work and theelectrode is zero,

as there will exist a'current between the electrodes of the conductorthat will maintain the arc. Thus, although the resultant current to thework will be a single phase alternating current with zero instantaneoustheinstant of reversal there will be a current flowi electrode of-the dierent phases w ch will tend to maintain the arc path to the work in astate of conductivity;

My invention will be better .understood sidered in connection with theaccompanying drawing, and its scope will be pointed out inthe'appended-claims.

Referring to the drawing, Figs. 1, 2, 3,

an electrode made of a single conducative to each other, as will besubbetween the tip? of the from the following description when oon-' and4'show diagrammatically several circuits. adapted to effect the purposeof the present invention; Fig. 5 shows a suitable electrode and holderfor use in practising my invention; and Fig. 6 shows another form ofwelding electrode that may be used.

The proposed arrangement in its simplest form consists of resistance andinductive reactance connected to the two conductors of an electrode andto thesupply circuit as diagrammaticall illustrated in Fig. 1. In thisfigure, 1 an 2 re resent the component parts of an electrode ormed oftwo conductors that are insulated from one another throughout their lenh. These conductors are connected throu a reactance 3 and a resistance 4to one terminal of a secondary 5 of a transformer 6. In this figure, theother terminal of the secondary5 is connected by a conductor 7 to thework 8. The transformer 6 is su plied with energy from a suitable source0 alternating current, not shown.- It is, of course, apparent that thetransformer 6 may be elimmated and the connection made directly to' anysuitable source. Either or both the resistance 3 or inductance 4 maybe'made adjustable in order to vary their eflect on the welding currentand control the phase'displacement existing between the currentssupplied'to the conductors of the'elec'trode. 7

It may be desirable under certain conditions to use in-the weldingcircuit a balance coil. Such an arrangement is shown in Fig.2.r Inthisfigure, one terminal of the secondary 5 of transformer 6 isconnected to a mid-point of a balance coil 9. The other terminals ofthis coil are connected through an inductance 3 and a resistance 4 tothe conductors 1 and 2 of. the welding electrode.

This balance coil serves to facilitate the striking, of the arc and tosecure approxi- 3 and a resistance and the work 8 is con- 100 nected toa mid-point of the transformer winding. In Fig. 4, the conductors 1 and2 are connected through inductance 3 and resistance 4 to the terminaland an intermediate point of the secondary Winding 5 of the transformer6 while the work 8 is connected to the other terminal of thesecondliteferring to Fig. 5, I have shown a suitable electrode andelectrode holder for use in practising my invention. The electrode 10comprises a core or inner portion 11 and a sheath or outer portion 12which is insulated by a suitable medium 13, which, if desired, may alsobe a flux, from the core member 11. The sheath is illustrated as openedat some point along its length and the insulation removed from the innermember so that a conductive contact may be made with the core and sheathmembers of the electrode by members 14 and 15 of an electrode holder 16.These members are insulated from one another by a bushing 17 whichtogether with these members is mounted in holder 18 which provides asuitable handle. The members 14 and 15 are provided with terminals'forconnecting the conductors of the electrode to the welding circuitaccording to some arrangement as above described. Member 15 comprises apipe or tube having its end portion cut diagonally and provided withnotches along its diagonal section, while member 14 is a rod locatedcentrally within member 15. The electrode is held by a wedging action inone of the grooves of member 15 by member 14. It is apparent that myinvention is not limited to any particular construction of electrodeholder.

Another form of electrode is shown in Fig. 6. This electrode is formedof two rectangular strips of suitable weld material 19 and 20 separatedby a suitable insulating material 21 which may at the same time serve asa binder to hold strips 19 and 20 together. This materialmay he a fluxas has been'noted with respect to the electrode described in Fig. 5.

While I have described certain arrangements for practising my invention,it is to be understood that in its broadest aspect the method ofconnection is immaterial as long as a difference in phase between thecurrents supplied to the conductors of the'electrode is brought about.One way of practising the invention is by applying high frequency to anelectrode such as shown in Fig. 5 when, due to the skin effect, thedesired difierence in phase between the arcs maintained by the electrodewill be automatically brought about.

It is to be noted that with my arrangement the work functions as oneelectrode with respect to each of the currents flowing in the conductorsof the welding electrode. The currents supplied to the welding electrodemay be out of phase with respect to each other to a greater or lessextent. The more out of phase they are the greater is the percentage oftotal heat which is generated at the electrode tip and the less is thepercentage of total heat that is generated in the work. With myarrangement, however, the apportionment of heat may be regulated bysuitably adjusting the constants of the circuits to secure a greater orless phase displacement between the currents supplied to the conductorsformin the weldlng electrode. If the phase displacement is great,considerable heat will be generated at the tip of the welding electrode.Such an arrangement would be useful when welding thin plates. If,however, greater heat is to be generated in the work, the relative phasedisplacement would be lessened. The invention may be applied to carbonarc welding as well as metallic arc welding and a non-consumingelectrode, such as tungsten, may be used.

While I have shown and described the use of reactance and resistance toadjust the electrical constants of the circuits feeding the weldingelectrode and thus secure the desired split-phase relationship, it is tobe understood that capacitance may be used in place of inductance orresistance to accomplish the desired effect of giving to the circuitsdifferent electrical constants.

What I claim as new and desire to secure by Letters Patent of the UnitedStates, is:

1. The method of welding with single phase alternating current whichcomprises" splitting the phase and maintaining an arc with the dephasedcurrents thus produced.

2. The method of electric welding wherein an arc is maintained bet-weenan electrode and the work by a single phase alternating current sourcewhich comprises dividing the welding current into a. plurality ofdephased component parts and maintaining with said component parts aplurality of arcs with relative phase displacement operating in parallelupon the same portion of the work.

I 3. The method of welding with single phase alternating current whichcomprises dividing the welding current into a plurality of dephasedcomponents, applying said dephased components to the individualconductors of a welding electrode comprising a plurality of conductorsinsulated from one another throughout their length and maintaining anare between said electrode and the work which is connected to thealternating current source.

4. Apparatus for electric arc welding comprising a source of singlephase alternatin current, means for connecting one termina of saidsource to'the work, a welding electrode formed of a plurality ofconductors insulated from one another throughout their length, and meanscomprisin a plurality of parallel circuits having di erent electrical1,035,704 I i 3 constants for connecting the other terminal terminal andmeans terminating at a luralof said source to the individual conductorsity of other arcing terminals for sp itting l of said electrode. thephase of the welding current between the 10 5. Apparatus for electricarc welding comsource and such other arcing terminals.

5 prising a source of single phase alternating In witness whereof, Ihave hereto set my current, means for connecting said source to handthlS 4th day of February, 1927. supply an arc with the work as onearcing E ARL PAXTON.

